This invention pertains to reformers and, in particular, to reformers for reforming fuels by catalytic activity.
It is well known in the prior art to utilize an elongated chamber filled with a suitable catalyst to reform fuels such as methanol. It is also known that in order for the reforming reaction to take place, the catalyst must be heated. Usually, heating of the catalyst is accomplished by conveying a heated gas along the chamber outer wall. Heat from the heated gas then penetrates radially into the chamber to the catalyst.
With this mode of heating, non-uniformities are found to occur in the temperature of the catalyst along the chamber length. In particular, the catalyst first past by the heated gas is found to be at a higher temperature than the catalyst which is later past by such heated gas. This is due to the fact that the heated gas decreases in temperature as it proceeds along the chamber outer wall and is also due to the fact that the catalyst itself is a relatively poor heat conductor. The heat lost by the heated gas is thus not compensated for by heat conduction through the catalyst and the aforesaid non-uniformity in heating results.
The effect of such heating, in turn, is reduced efficiency in the reforming process. Furthermore, efforts to increase this efficiency by increasing the temperature of the heated gas are limited by the need to maintain the temperature at the forward end of the chamber below that which would be harmful to the catalyst.
It is therefore an object of the present invention to provide a fuel reformer having a greater uniformity in catalyst temperature.
It is also an object of the present invention to provide a fuel reformer whose average heating temperature is higher than that of prior art reformers.